Galle, J., & Warren, P. (1989). Ecology discovery activities kit: A complete teaching unit for grades 4-8. Center for Applied Research in Education.
Chicago Style aipamenaGalle, Janet, and Patricia Warren. Ecology Discovery Activities Kit: A Complete Teaching Unit for Grades 4-8. West Nyack, N.Y: Center for Applied Research in Education, 1989.
MLA aipamenaGalle, Janet, and Patricia Warren. Ecology Discovery Activities Kit: A Complete Teaching Unit for Grades 4-8. Center for Applied Research in Education, 1989.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.